level: simple
...7.....1...........43.2..........6...5.9.........418....81.....2....5..4....3.. | initial |
264715839137892645598436271423178596816549723759623418375281964982364157641957382 | solved |
level: simple
From http://theconversation.com/good-at-sudoku-heres-some-youll-never-complete-5234 Check per request from http://puzzling.stackexchange.com/users/35827/simon-streicher in a comment to http://puzzling.stackexchange.com/a/8032/9013